#include <stdio.h>
#include <math.h>

int main()
{
    int n;
    double num, decimal_part, sum = 0.0;
    scanf("%d", &n);
    for (int i = 0; i < n; i++)
    {
        scanf("%lf", &num);
        double integer_part = floor(num);
        decimal_part = num - integer_part;
        sum += decimal_part;
    }
    printf("%.2f", sum);
    return 0;
}